This invention relates to an automatic original circulating and feeding apparatus in a copying machine.
Some of the conventional copying machines is provided with an automatic original circulating and feeding apparatus, i.e. what is called RADF, which, for the purpose of improving the original processing capacity of a copying machine, permits a plurality of originals to be copied in a plurality of cycles by causing the originals to be automatically fed and recovered cyclically.
The RADF of this operating principle is generally provided with a frictional type paper separating mechanism for successively separating one by one originals piled up on an original feeding base from the lowermost original and forwarding them one by one to the copying machine.
Now, the conventional RADF is considered here as applied to the copying of double-faced originals. These double-faced originals piled up in the consecutive order of page numbers are set on the original feeding base in such a manner that the first page will form the uppermost original turned upwardly and the originals will be forwarded to the copying machine in the reverse order of page numbers. In this case, since the last page which is copied first is turned downwardly on the original feeding base, it must be turned upside down before it is forwarded onto a contact glass and set in the copying position. This is because the penultimate page constitutes itself a downwardly turned copy surface on the contact glass when this conveyance of the page is made on a turn feed route. The original in this state, therefore, is turned upside down on a switchback type route so that it will be placed on the contact glass with the last page turned downwardly. This operation inevitably requires each original to be conveyed and set through an idle step which has no part at all in the actual copying machine, entailing waste of time and impairing efficiency of the copying operation. Again when the penultimate page is to be copied, the same original must be sent through the same route before it is set on the contact glass. While one original is being copied, none of the feed routes is allowed to admit the next original. Thus, the conventional RADF necessitates a waiting time and, in this respect, operates with a slow processing rate. Particularly when the copying machine proper is capable of a high-speed processing, it is compelled to be operated at a lowered speed because the RADF of such a slow processing rate cannot keep pace with the high-speed operation of the copying machine. As the result, the use of the RADF prevents any effort to improve the CPM (copies per minute; efficiency of copying work).
When the double-faced originals are piled up consecutively in the order of page numbers with each of the originals turned upside down, the originals can be forwarded solely through a feed route to the copying machine. This setup, however, entails a troublesome work of causing all the originals to set severally upside down.
Even in the case of single-faced originals, they are fed out and recovered consecutively in the order of page numbers with the original-bearing face of each original turned upwardly. Since the time to start feeding the next original is restricted for the purpose of preventing two originals from passing each other on the contact glass, this arrangement also impedes the improvement of CPM.